[S390] appldata/extmem/kvm: add missing GFP_KERNEL flag
[linux-2.6.git] / arch / s390 / mm / extmem.c
1 /*
2  * File...........: arch/s390/mm/extmem.c
3  * Author(s)......: Carsten Otte <cotte@de.ibm.com>
4  *                  Rob M van der Heij <rvdheij@nl.ibm.com>
5  *                  Steven Shultz <shultzss@us.ibm.com>
6  * Bugreports.to..: <Linux390@de.ibm.com>
7  * (C) IBM Corporation 2002-2004
8  */
9
10 #define KMSG_COMPONENT "extmem"
11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12
13 #include <linux/kernel.h>
14 #include <linux/string.h>
15 #include <linux/spinlock.h>
16 #include <linux/list.h>
17 #include <linux/slab.h>
18 #include <linux/module.h>
19 #include <linux/bootmem.h>
20 #include <linux/ctype.h>
21 #include <linux/ioport.h>
22 #include <asm/page.h>
23 #include <asm/pgtable.h>
24 #include <asm/ebcdic.h>
25 #include <asm/errno.h>
26 #include <asm/extmem.h>
27 #include <asm/cpcmd.h>
28 #include <asm/setup.h>
29
30 #define DCSS_LOADSHR    0x00
31 #define DCSS_LOADNSR    0x04
32 #define DCSS_PURGESEG   0x08
33 #define DCSS_FINDSEG    0x0c
34 #define DCSS_LOADNOLY   0x10
35 #define DCSS_SEGEXT     0x18
36 #define DCSS_LOADSHRX   0x20
37 #define DCSS_LOADNSRX   0x24
38 #define DCSS_FINDSEGX   0x2c
39 #define DCSS_SEGEXTX    0x38
40 #define DCSS_FINDSEGA   0x0c
41
42 struct qrange {
43         unsigned long  start; /* last byte type */
44         unsigned long  end;   /* last byte reserved */
45 };
46
47 struct qout64 {
48         unsigned long segstart;
49         unsigned long segend;
50         int segcnt;
51         int segrcnt;
52         struct qrange range[6];
53 };
54
55 #ifdef CONFIG_64BIT
56 struct qrange_old {
57         unsigned int start; /* last byte type */
58         unsigned int end;   /* last byte reserved */
59 };
60
61 /* output area format for the Diag x'64' old subcode x'18' */
62 struct qout64_old {
63         int segstart;
64         int segend;
65         int segcnt;
66         int segrcnt;
67         struct qrange_old range[6];
68 };
69 #endif
70
71 struct qin64 {
72         char qopcode;
73         char rsrv1[3];
74         char qrcode;
75         char rsrv2[3];
76         char qname[8];
77         unsigned int qoutptr;
78         short int qoutlen;
79 };
80
81 struct dcss_segment {
82         struct list_head list;
83         char dcss_name[8];
84         char res_name[15];
85         unsigned long start_addr;
86         unsigned long end;
87         atomic_t ref_count;
88         int do_nonshared;
89         unsigned int vm_segtype;
90         struct qrange range[6];
91         int segcnt;
92         struct resource *res;
93 };
94
95 static DEFINE_MUTEX(dcss_lock);
96 static LIST_HEAD(dcss_list);
97 static char *segtype_string[] = { "SW", "EW", "SR", "ER", "SN", "EN", "SC",
98                                         "EW/EN-MIXED" };
99 static int loadshr_scode, loadnsr_scode, findseg_scode;
100 static int segext_scode, purgeseg_scode;
101 static int scode_set;
102
103 /* set correct Diag x'64' subcodes. */
104 static int
105 dcss_set_subcodes(void)
106 {
107 #ifdef CONFIG_64BIT
108         char *name = kmalloc(8 * sizeof(char), GFP_KERNEL | GFP_DMA);
109         unsigned long rx, ry;
110         int rc;
111
112         if (name == NULL)
113                 return -ENOMEM;
114
115         rx = (unsigned long) name;
116         ry = DCSS_FINDSEGX;
117
118         strcpy(name, "dummy");
119         asm volatile(
120                 "       diag    %0,%1,0x64\n"
121                 "0:     ipm     %2\n"
122                 "       srl     %2,28\n"
123                 "       j       2f\n"
124                 "1:     la      %2,3\n"
125                 "2:\n"
126                 EX_TABLE(0b, 1b)
127                 : "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
128
129         kfree(name);
130         /* Diag x'64' new subcodes are supported, set to new subcodes */
131         if (rc != 3) {
132                 loadshr_scode = DCSS_LOADSHRX;
133                 loadnsr_scode = DCSS_LOADNSRX;
134                 purgeseg_scode = DCSS_PURGESEG;
135                 findseg_scode = DCSS_FINDSEGX;
136                 segext_scode = DCSS_SEGEXTX;
137                 return 0;
138         }
139 #endif
140         /* Diag x'64' new subcodes are not supported, set to old subcodes */
141         loadshr_scode = DCSS_LOADNOLY;
142         loadnsr_scode = DCSS_LOADNSR;
143         purgeseg_scode = DCSS_PURGESEG;
144         findseg_scode = DCSS_FINDSEG;
145         segext_scode = DCSS_SEGEXT;
146         return 0;
147 }
148
149 /*
150  * Create the 8 bytes, ebcdic VM segment name from
151  * an ascii name.
152  */
153 static void
154 dcss_mkname(char *name, char *dcss_name)
155 {
156         int i;
157
158         for (i = 0; i < 8; i++) {
159                 if (name[i] == '\0')
160                         break;
161                 dcss_name[i] = toupper(name[i]);
162         };
163         for (; i < 8; i++)
164                 dcss_name[i] = ' ';
165         ASCEBC(dcss_name, 8);
166 }
167
168
169 /*
170  * search all segments in dcss_list, and return the one
171  * namend *name. If not found, return NULL.
172  */
173 static struct dcss_segment *
174 segment_by_name (char *name)
175 {
176         char dcss_name[9];
177         struct list_head *l;
178         struct dcss_segment *tmp, *retval = NULL;
179
180         BUG_ON(!mutex_is_locked(&dcss_lock));
181         dcss_mkname (name, dcss_name);
182         list_for_each (l, &dcss_list) {
183                 tmp = list_entry (l, struct dcss_segment, list);
184                 if (memcmp(tmp->dcss_name, dcss_name, 8) == 0) {
185                         retval = tmp;
186                         break;
187                 }
188         }
189         return retval;
190 }
191
192
193 /*
194  * Perform a function on a dcss segment.
195  */
196 static inline int
197 dcss_diag(int *func, void *parameter,
198            unsigned long *ret1, unsigned long *ret2)
199 {
200         unsigned long rx, ry;
201         int rc;
202
203         if (scode_set == 0) {
204                 rc = dcss_set_subcodes();
205                 if (rc < 0)
206                         return rc;
207                 scode_set = 1;
208         }
209         rx = (unsigned long) parameter;
210         ry = (unsigned long) *func;
211
212 #ifdef CONFIG_64BIT
213         /* 64-bit Diag x'64' new subcode, keep in 64-bit addressing mode */
214         if (*func > DCSS_SEGEXT)
215                 asm volatile(
216                         "       diag    %0,%1,0x64\n"
217                         "       ipm     %2\n"
218                         "       srl     %2,28\n"
219                         : "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
220         /* 31-bit Diag x'64' old subcode, switch to 31-bit addressing mode */
221         else
222                 asm volatile(
223                         "       sam31\n"
224                         "       diag    %0,%1,0x64\n"
225                         "       sam64\n"
226                         "       ipm     %2\n"
227                         "       srl     %2,28\n"
228                         : "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
229 #else
230         asm volatile(
231                 "       diag    %0,%1,0x64\n"
232                 "       ipm     %2\n"
233                 "       srl     %2,28\n"
234                 : "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
235 #endif
236         *ret1 = rx;
237         *ret2 = ry;
238         return rc;
239 }
240
241 static inline int
242 dcss_diag_translate_rc (int vm_rc) {
243         if (vm_rc == 44)
244                 return -ENOENT;
245         return -EIO;
246 }
247
248
249 /* do a diag to get info about a segment.
250  * fills start_address, end and vm_segtype fields
251  */
252 static int
253 query_segment_type (struct dcss_segment *seg)
254 {
255         unsigned long dummy, vmrc;
256         int diag_cc, rc, i;
257         struct qout64 *qout;
258         struct qin64 *qin;
259
260         qin = kmalloc(sizeof(*qin), GFP_KERNEL | GFP_DMA);
261         qout = kmalloc(sizeof(*qout), GFP_KERNEL | GFP_DMA);
262         if ((qin == NULL) || (qout == NULL)) {
263                 rc = -ENOMEM;
264                 goto out_free;
265         }
266
267         /* initialize diag input parameters */
268         qin->qopcode = DCSS_FINDSEGA;
269         qin->qoutptr = (unsigned long) qout;
270         qin->qoutlen = sizeof(struct qout64);
271         memcpy (qin->qname, seg->dcss_name, 8);
272
273         diag_cc = dcss_diag(&segext_scode, qin, &dummy, &vmrc);
274
275         if (diag_cc < 0) {
276                 rc = diag_cc;
277                 goto out_free;
278         }
279         if (diag_cc > 1) {
280                 pr_warning("Querying a DCSS type failed with rc=%ld\n", vmrc);
281                 rc = dcss_diag_translate_rc (vmrc);
282                 goto out_free;
283         }
284
285 #ifdef CONFIG_64BIT
286         /* Only old format of output area of Diagnose x'64' is supported,
287            copy data for the new format. */
288         if (segext_scode == DCSS_SEGEXT) {
289                 struct qout64_old *qout_old;
290                 qout_old = kzalloc(sizeof(*qout_old), GFP_KERNEL | GFP_DMA);
291                 if (qout_old == NULL) {
292                         rc = -ENOMEM;
293                         goto out_free;
294                 }
295                 memcpy(qout_old, qout, sizeof(struct qout64_old));
296                 qout->segstart = (unsigned long) qout_old->segstart;
297                 qout->segend = (unsigned long) qout_old->segend;
298                 qout->segcnt = qout_old->segcnt;
299                 qout->segrcnt = qout_old->segrcnt;
300
301                 if (qout->segcnt > 6)
302                         qout->segrcnt = 6;
303                 for (i = 0; i < qout->segrcnt; i++) {
304                         qout->range[i].start =
305                                 (unsigned long) qout_old->range[i].start;
306                         qout->range[i].end =
307                                 (unsigned long) qout_old->range[i].end;
308                 }
309                 kfree(qout_old);
310         }
311 #endif
312         if (qout->segcnt > 6) {
313                 rc = -EOPNOTSUPP;
314                 goto out_free;
315         }
316
317         if (qout->segcnt == 1) {
318                 seg->vm_segtype = qout->range[0].start & 0xff;
319         } else {
320                 /* multi-part segment. only one type supported here:
321                     - all parts are contiguous
322                     - all parts are either EW or EN type
323                     - maximum 6 parts allowed */
324                 unsigned long start = qout->segstart >> PAGE_SHIFT;
325                 for (i=0; i<qout->segcnt; i++) {
326                         if (((qout->range[i].start & 0xff) != SEG_TYPE_EW) &&
327                             ((qout->range[i].start & 0xff) != SEG_TYPE_EN)) {
328                                 rc = -EOPNOTSUPP;
329                                 goto out_free;
330                         }
331                         if (start != qout->range[i].start >> PAGE_SHIFT) {
332                                 rc = -EOPNOTSUPP;
333                                 goto out_free;
334                         }
335                         start = (qout->range[i].end >> PAGE_SHIFT) + 1;
336                 }
337                 seg->vm_segtype = SEG_TYPE_EWEN;
338         }
339
340         /* analyze diag output and update seg */
341         seg->start_addr = qout->segstart;
342         seg->end = qout->segend;
343
344         memcpy (seg->range, qout->range, 6*sizeof(struct qrange));
345         seg->segcnt = qout->segcnt;
346
347         rc = 0;
348
349  out_free:
350         kfree(qin);
351         kfree(qout);
352         return rc;
353 }
354
355 /*
356  * get info about a segment
357  * possible return values:
358  * -ENOSYS  : we are not running on VM
359  * -EIO     : could not perform query diagnose
360  * -ENOENT  : no such segment
361  * -EOPNOTSUPP: multi-part segment cannot be used with linux
362  * -ENOMEM  : out of memory
363  * 0 .. 6   : type of segment as defined in include/asm-s390/extmem.h
364  */
365 int
366 segment_type (char* name)
367 {
368         int rc;
369         struct dcss_segment seg;
370
371         if (!MACHINE_IS_VM)
372                 return -ENOSYS;
373
374         dcss_mkname(name, seg.dcss_name);
375         rc = query_segment_type (&seg);
376         if (rc < 0)
377                 return rc;
378         return seg.vm_segtype;
379 }
380
381 /*
382  * check if segment collides with other segments that are currently loaded
383  * returns 1 if this is the case, 0 if no collision was found
384  */
385 static int
386 segment_overlaps_others (struct dcss_segment *seg)
387 {
388         struct list_head *l;
389         struct dcss_segment *tmp;
390
391         BUG_ON(!mutex_is_locked(&dcss_lock));
392         list_for_each(l, &dcss_list) {
393                 tmp = list_entry(l, struct dcss_segment, list);
394                 if ((tmp->start_addr >> 20) > (seg->end >> 20))
395                         continue;
396                 if ((tmp->end >> 20) < (seg->start_addr >> 20))
397                         continue;
398                 if (seg == tmp)
399                         continue;
400                 return 1;
401         }
402         return 0;
403 }
404
405 /*
406  * real segment loading function, called from segment_load
407  */
408 static int
409 __segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long *end)
410 {
411         unsigned long start_addr, end_addr, dummy;
412         struct dcss_segment *seg;
413         int rc, diag_cc;
414
415         seg = kmalloc(sizeof(*seg), GFP_KERNEL | GFP_DMA);
416         if (seg == NULL) {
417                 rc = -ENOMEM;
418                 goto out;
419         }
420         dcss_mkname (name, seg->dcss_name);
421         rc = query_segment_type (seg);
422         if (rc < 0)
423                 goto out_free;
424
425         if (loadshr_scode == DCSS_LOADSHRX) {
426                 if (segment_overlaps_others(seg)) {
427                         rc = -EBUSY;
428                         goto out_free;
429                 }
430         }
431
432         rc = vmem_add_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
433
434         if (rc)
435                 goto out_free;
436
437         seg->res = kzalloc(sizeof(struct resource), GFP_KERNEL);
438         if (seg->res == NULL) {
439                 rc = -ENOMEM;
440                 goto out_shared;
441         }
442         seg->res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
443         seg->res->start = seg->start_addr;
444         seg->res->end = seg->end;
445         memcpy(&seg->res_name, seg->dcss_name, 8);
446         EBCASC(seg->res_name, 8);
447         seg->res_name[8] = '\0';
448         strncat(seg->res_name, " (DCSS)", 7);
449         seg->res->name = seg->res_name;
450         rc = seg->vm_segtype;
451         if (rc == SEG_TYPE_SC ||
452             ((rc == SEG_TYPE_SR || rc == SEG_TYPE_ER) && !do_nonshared))
453                 seg->res->flags |= IORESOURCE_READONLY;
454         if (request_resource(&iomem_resource, seg->res)) {
455                 rc = -EBUSY;
456                 kfree(seg->res);
457                 goto out_shared;
458         }
459
460         if (do_nonshared)
461                 diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
462                                 &start_addr, &end_addr);
463         else
464                 diag_cc = dcss_diag(&loadshr_scode, seg->dcss_name,
465                                 &start_addr, &end_addr);
466         if (diag_cc < 0) {
467                 dcss_diag(&purgeseg_scode, seg->dcss_name,
468                                 &dummy, &dummy);
469                 rc = diag_cc;
470                 goto out_resource;
471         }
472         if (diag_cc > 1) {
473                 pr_warning("Loading DCSS %s failed with rc=%ld\n", name,
474                            end_addr);
475                 rc = dcss_diag_translate_rc(end_addr);
476                 dcss_diag(&purgeseg_scode, seg->dcss_name,
477                                 &dummy, &dummy);
478                 goto out_resource;
479         }
480         seg->start_addr = start_addr;
481         seg->end = end_addr;
482         seg->do_nonshared = do_nonshared;
483         atomic_set(&seg->ref_count, 1);
484         list_add(&seg->list, &dcss_list);
485         *addr = seg->start_addr;
486         *end  = seg->end;
487         if (do_nonshared)
488                 pr_info("DCSS %s of range %p to %p and type %s loaded as "
489                         "exclusive-writable\n", name, (void*) seg->start_addr,
490                         (void*) seg->end, segtype_string[seg->vm_segtype]);
491         else {
492                 pr_info("DCSS %s of range %p to %p and type %s loaded in "
493                         "shared access mode\n", name, (void*) seg->start_addr,
494                         (void*) seg->end, segtype_string[seg->vm_segtype]);
495         }
496         goto out;
497  out_resource:
498         release_resource(seg->res);
499         kfree(seg->res);
500  out_shared:
501         vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
502  out_free:
503         kfree(seg);
504  out:
505         return rc;
506 }
507
508 /*
509  * this function loads a DCSS segment
510  * name         : name of the DCSS
511  * do_nonshared : 0 indicates that the dcss should be shared with other linux images
512  *                1 indicates that the dcss should be exclusive for this linux image
513  * addr         : will be filled with start address of the segment
514  * end          : will be filled with end address of the segment
515  * return values:
516  * -ENOSYS  : we are not running on VM
517  * -EIO     : could not perform query or load diagnose
518  * -ENOENT  : no such segment
519  * -EOPNOTSUPP: multi-part segment cannot be used with linux
520  * -ENOSPC  : segment cannot be used (overlaps with storage)
521  * -EBUSY   : segment can temporarily not be used (overlaps with dcss)
522  * -ERANGE  : segment cannot be used (exceeds kernel mapping range)
523  * -EPERM   : segment is currently loaded with incompatible permissions
524  * -ENOMEM  : out of memory
525  * 0 .. 6   : type of segment as defined in include/asm-s390/extmem.h
526  */
527 int
528 segment_load (char *name, int do_nonshared, unsigned long *addr,
529                 unsigned long *end)
530 {
531         struct dcss_segment *seg;
532         int rc;
533
534         if (!MACHINE_IS_VM)
535                 return -ENOSYS;
536
537         mutex_lock(&dcss_lock);
538         seg = segment_by_name (name);
539         if (seg == NULL)
540                 rc = __segment_load (name, do_nonshared, addr, end);
541         else {
542                 if (do_nonshared == seg->do_nonshared) {
543                         atomic_inc(&seg->ref_count);
544                         *addr = seg->start_addr;
545                         *end  = seg->end;
546                         rc    = seg->vm_segtype;
547                 } else {
548                         *addr = *end = 0;
549                         rc    = -EPERM;
550                 }
551         }
552         mutex_unlock(&dcss_lock);
553         return rc;
554 }
555
556 /*
557  * this function modifies the shared state of a DCSS segment. note that
558  * name         : name of the DCSS
559  * do_nonshared : 0 indicates that the dcss should be shared with other linux images
560  *                1 indicates that the dcss should be exclusive for this linux image
561  * return values:
562  * -EIO     : could not perform load diagnose (segment gone!)
563  * -ENOENT  : no such segment (segment gone!)
564  * -EAGAIN  : segment is in use by other exploiters, try later
565  * -EINVAL  : no segment with the given name is currently loaded - name invalid
566  * -EBUSY   : segment can temporarily not be used (overlaps with dcss)
567  * 0        : operation succeeded
568  */
569 int
570 segment_modify_shared (char *name, int do_nonshared)
571 {
572         struct dcss_segment *seg;
573         unsigned long start_addr, end_addr, dummy;
574         int rc, diag_cc;
575
576         mutex_lock(&dcss_lock);
577         seg = segment_by_name (name);
578         if (seg == NULL) {
579                 rc = -EINVAL;
580                 goto out_unlock;
581         }
582         if (do_nonshared == seg->do_nonshared) {
583                 pr_info("DCSS %s is already in the requested access "
584                         "mode\n", name);
585                 rc = 0;
586                 goto out_unlock;
587         }
588         if (atomic_read (&seg->ref_count) != 1) {
589                 pr_warning("DCSS %s is in use and cannot be reloaded\n",
590                            name);
591                 rc = -EAGAIN;
592                 goto out_unlock;
593         }
594         release_resource(seg->res);
595         if (do_nonshared)
596                 seg->res->flags &= ~IORESOURCE_READONLY;
597         else
598                 if (seg->vm_segtype == SEG_TYPE_SR ||
599                     seg->vm_segtype == SEG_TYPE_ER)
600                         seg->res->flags |= IORESOURCE_READONLY;
601
602         if (request_resource(&iomem_resource, seg->res)) {
603                 pr_warning("DCSS %s overlaps with used memory resources "
604                            "and cannot be reloaded\n", name);
605                 rc = -EBUSY;
606                 kfree(seg->res);
607                 goto out_del_mem;
608         }
609
610         dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
611         if (do_nonshared)
612                 diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
613                                 &start_addr, &end_addr);
614         else
615                 diag_cc = dcss_diag(&loadshr_scode, seg->dcss_name,
616                                 &start_addr, &end_addr);
617         if (diag_cc < 0) {
618                 rc = diag_cc;
619                 goto out_del_res;
620         }
621         if (diag_cc > 1) {
622                 pr_warning("Reloading DCSS %s failed with rc=%ld\n", name,
623                            end_addr);
624                 rc = dcss_diag_translate_rc(end_addr);
625                 goto out_del_res;
626         }
627         seg->start_addr = start_addr;
628         seg->end = end_addr;
629         seg->do_nonshared = do_nonshared;
630         rc = 0;
631         goto out_unlock;
632  out_del_res:
633         release_resource(seg->res);
634         kfree(seg->res);
635  out_del_mem:
636         vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
637         list_del(&seg->list);
638         dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
639         kfree(seg);
640  out_unlock:
641         mutex_unlock(&dcss_lock);
642         return rc;
643 }
644
645 /*
646  * Decrease the use count of a DCSS segment and remove
647  * it from the address space if nobody is using it
648  * any longer.
649  */
650 void
651 segment_unload(char *name)
652 {
653         unsigned long dummy;
654         struct dcss_segment *seg;
655
656         if (!MACHINE_IS_VM)
657                 return;
658
659         mutex_lock(&dcss_lock);
660         seg = segment_by_name (name);
661         if (seg == NULL) {
662                 pr_err("Unloading unknown DCSS %s failed\n", name);
663                 goto out_unlock;
664         }
665         if (atomic_dec_return(&seg->ref_count) != 0)
666                 goto out_unlock;
667         release_resource(seg->res);
668         kfree(seg->res);
669         vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
670         list_del(&seg->list);
671         dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
672         kfree(seg);
673 out_unlock:
674         mutex_unlock(&dcss_lock);
675 }
676
677 /*
678  * save segment content permanently
679  */
680 void
681 segment_save(char *name)
682 {
683         struct dcss_segment *seg;
684         int startpfn = 0;
685         int endpfn = 0;
686         char cmd1[160];
687         char cmd2[80];
688         int i, response;
689
690         if (!MACHINE_IS_VM)
691                 return;
692
693         mutex_lock(&dcss_lock);
694         seg = segment_by_name (name);
695
696         if (seg == NULL) {
697                 pr_err("Saving unknown DCSS %s failed\n", name);
698                 goto out;
699         }
700
701         startpfn = seg->start_addr >> PAGE_SHIFT;
702         endpfn = (seg->end) >> PAGE_SHIFT;
703         sprintf(cmd1, "DEFSEG %s", name);
704         for (i=0; i<seg->segcnt; i++) {
705                 sprintf(cmd1+strlen(cmd1), " %lX-%lX %s",
706                         seg->range[i].start >> PAGE_SHIFT,
707                         seg->range[i].end >> PAGE_SHIFT,
708                         segtype_string[seg->range[i].start & 0xff]);
709         }
710         sprintf(cmd2, "SAVESEG %s", name);
711         response = 0;
712         cpcmd(cmd1, NULL, 0, &response);
713         if (response) {
714                 pr_err("Saving a DCSS failed with DEFSEG response code "
715                        "%i\n", response);
716                 goto out;
717         }
718         cpcmd(cmd2, NULL, 0, &response);
719         if (response) {
720                 pr_err("Saving a DCSS failed with SAVESEG response code "
721                        "%i\n", response);
722                 goto out;
723         }
724 out:
725         mutex_unlock(&dcss_lock);
726 }
727
728 /*
729  * print appropriate error message for segment_load()/segment_type()
730  * return code
731  */
732 void segment_warning(int rc, char *seg_name)
733 {
734         switch (rc) {
735         case -ENOENT:
736                 pr_err("DCSS %s cannot be loaded or queried\n", seg_name);
737                 break;
738         case -ENOSYS:
739                 pr_err("DCSS %s cannot be loaded or queried without "
740                        "z/VM\n", seg_name);
741                 break;
742         case -EIO:
743                 pr_err("Loading or querying DCSS %s resulted in a "
744                        "hardware error\n", seg_name);
745                 break;
746         case -EOPNOTSUPP:
747                 pr_err("DCSS %s has multiple page ranges and cannot be "
748                        "loaded or queried\n", seg_name);
749                 break;
750         case -ENOSPC:
751                 pr_err("DCSS %s overlaps with used storage and cannot "
752                        "be loaded\n", seg_name);
753                 break;
754         case -EBUSY:
755                 pr_err("%s needs used memory resources and cannot be "
756                        "loaded or queried\n", seg_name);
757                 break;
758         case -EPERM:
759                 pr_err("DCSS %s is already loaded in a different access "
760                        "mode\n", seg_name);
761                 break;
762         case -ENOMEM:
763                 pr_err("There is not enough memory to load or query "
764                        "DCSS %s\n", seg_name);
765                 break;
766         case -ERANGE:
767                 pr_err("DCSS %s exceeds the kernel mapping range (%lu) "
768                        "and cannot be loaded\n", seg_name, VMEM_MAX_PHYS);
769                 break;
770         default:
771                 break;
772         }
773 }
774
775 EXPORT_SYMBOL(segment_load);
776 EXPORT_SYMBOL(segment_unload);
777 EXPORT_SYMBOL(segment_save);
778 EXPORT_SYMBOL(segment_type);
779 EXPORT_SYMBOL(segment_modify_shared);
780 EXPORT_SYMBOL(segment_warning);